Flip switches on a 5x5 board of amber lights until the whole grid goes dark, using as few presses as you can.
Light Switch Grid gives you a 5x5 panel of glowing amber lights and one job: make every cell go dark. Each cell works like a switch, but a press also flips the cells directly above, below, left and right of it. Diagonal cells are left alone.
That single rule is what makes it tricky. Turning one light off can turn three others on, so random tapping rarely gets you anywhere. The fun is in working out which handful of presses clears the whole board.
Rules in brief
When you press a cell, it and its side neighbors all swap state. A lit cell turns off and a dark cell turns on. Cells along the edge have fewer neighbors, and a corner cell only touches two.
A status line keeps a running tally of lit cells, and a counter adds up your presses. When the board is fully dark, the game tells you how many moves it took. If that beats your old record for the level, it is saved as your new Best.
You can pick Easy, Medium or Hard. Under the hood, each puzzle starts as a dark board that gets scrambled with 3, 6 or 10 presses, which means every board has a solution. The opening board at each level is picked from the UTC date, so you see that one layout until the date rolls over. Press “new” any time for a random layout.
A reliable way to solve it
Most boards fall to a simple method that works from the top down.
- Look at the top row. For every light that is on, press the cell right under it.
- Do the same for the second row, then the third and fourth. The lights get pushed down toward the bottom.
- Whatever is left in the bottom row is a clue. Note the pattern, press reset, press the matching cells in the top row, and then push down again.
- Skip any cell you would press twice. Two presses cancel each other, so they only waste moves.
The order of your presses never changes the final result. Only the set of cells you pressed matters. That means you can plan the whole solution in your head before you touch the board.
Undo, reset and other buttons
Undo reverses a single press, which is handy for a single slip. If a whole attempt goes wrong, reset is quicker, since it restores the starting pattern in one step and clears your move count.
The “? man” button opens a help page in the style of an old terminal manual. Close it with the x, by clicking outside the box, or with Esc or Q on a keyboard. The color scheme also switches to match whichever theme your device uses.
Who it suits
This is a good pick if you like quiet puzzles with no clock and no luck. Easy boards make a nice warm-up for a short break. Hard boards reward players who enjoy finding patterns, and chasing a lower Best gives you a reason to replay a board you have already solved.
Controls
| Action | Mouse | Touch |
|---|---|---|
| Press a cell (flips it and its side neighbors) | Click the cell | Tap the cell |
| Take back the last press | Click "undo" | Tap "undo" |
| Return to the starting pattern | Click "reset" | Tap "reset" |
| Pick a difficulty or roll a random puzzle | Click Easy, Medium, Hard or "new" | Tap Easy, Medium, Hard or "new" |
| Open or close the help page | Click "? man", then the × or outside the box | Tap "? man", then the × or outside the box |
Light Switch Grid FAQ
Does Light Switch Grid work on a phone or Chromebook?
Yes. It runs with a mouse or a touchscreen, so a Chromebook, tablet or phone all work. The cells are big enough to tap with a thumb. On a phone, hold it upright so the board and the buttons under it fit on the screen together.
Does the game remember my scores?
It does. Your lowest move count for each difficulty is stored in your browser, and so is the level you chose last. If you clear your browser data or switch to another device, those records start over.
How long does one puzzle take?
Easy boards are scrambled with only three presses, so they tend to be short. Hard boards start from ten presses and take longer to untangle. There is no timer, so you can think as long as you like.
What should I do if I get stuck?
Press reset to bring back the exact starting pattern and set your move count to zero. Then try the row-by-row method described on this page. You can also open the help page with the "? man" button for a quick reminder of the rules.
